Multi-functional joint brace

ABSTRACT

A multi-functional brace for a joint includes a releasable locking mechanism that allows the brace to be set for static stretch of the joint in either flexion or extension, and a range of motion assembly that allows for free movement of the joint through its natural axis over a controlled range of motion when the locking mechanism is released.

CROSS REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation of U.S. patent applicationSer. No. 10/357,990 filed on Feb. 4, 2003, entitled “Multi-FunctionalJoint Brace”. The entire teachings of the above-identified applicationare incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. The Field of the Invention

The present invention relates generally to joint support devices, and inparticular, to a multi-functional joint brace that protects the jointfrom internal and external forces and provides for immobilization,static stretching of the joint alternately in flexion and extension, andfree movement of the joint over a controlled range of motion.

2. Description of the Related Art

In the health care field, joint support devices are used to protect andpromote healing of damaged joints. A wide variety of externally appliedsupports and braces are known and used in the field. One variety ofdevices protects joints by immobilization. These devices also canprotect the joint by providing a rigid surface that deflects the energyfrom an external force. A traditional plaster cast is a joint supportdevice that protects by immobilization and by providing a rigid shell.

Another variety of devices promotes healing of a damaged joint byproviding controlled stretching of a joint in either a flexed orextended position. One such type of brace locks the joint in an extendedor flexed position, and provides dynamic stretching to the joint bymeans of a spring that exerts a constant torque against the joint as thejoint relaxes into the flexed or extended position. The angle of flexionor extension can be gradually adjusted over a range of angles as a jointheals. Such dynamic stretching devices are shown, for example, in U.S.Pat. Nos. 5,399,154 and 5,437,619.

Another type of device provides static rather than dynamic stretching ofa joint in either flexion or extension. The device is set at apredetermined angle of flexion or extension and then locked intoposition to provide static stretching of the joint, which strengthensthe muscles and tendons around the joint, but without the use of springsor other means that provide a constant torque against the joint. Theangle of flexion or extension can be gradually adjusted as the jointheals. Such devices are shown, for example, in DE 196 06 092 A1, U.S.Pat. Nos. 5,885,235, 5,938,629, 6,039,709 and 6,375,632.

Yet another variety of device promotes healing of a damaged joint byallowing a joint to move freely along its axis of natural movement,while limiting twisting or torsional movement of the joint outside itsaxis of natural movement. The free movement along the natural axis ofthe joint can be limited to a predetermined range of flexion orextension. Free movement along this controlled range of motion canstrengthen the tendons and muscles in a damaged joint while preventingthe weakened joint from being damaged by twisting or moving outside ofits natural axis of movement.

The expense and inconvenience of repairing and rehabilitating a joint isincreased if more than one brace must be used during the healingprocess. For example, a rigid cast might be applied first to a brokenjoint to immobilize the joint for a period of time. Then, a brace thatprovides a static flexion stretch of the joint might be required afterthe rigid cast is removed, and yet another brace that provides a staticextension stretch of the joint also might be required. To furtherrehabilitate a damaged joint, a brace that allows controlled free motionof the joint also might be needed. The use of different bracesthroughout the rehabilitation process can be inconvenient for both thehealth-care provider and the patient, and can increase the time andexpense required to fully heal a damaged joint. Currently availablejoint support devices do not combine different rehabilitative featuresinto one device.

It is thus one object of the invention to provide a single joint bracedevice that performs more than one rehabilitative function on a damagedjoint.

It is another object of the invention to provide a lightweight,streamlined joint brace device that is more comfortable than prior artdevices.

Many of the currently available joint support devices do not interchangeeasily between joints on the left and right sides of the body, and donot interchange easily between persons of different sizes. It istherefore still another object of the invention to provide a joint bracedevice that can be used on a joint on either side of the body, and thatcan be used on patients of various sizes.

SUMMARY OF THE INVENTION

The present invention overcomes the disadvantages in the prior art byproviding a light-weight and streamlined joint brace device that canperform different rehabilitative functions. The joint brace disclosedherein achieves advancements over the prior art because of its uniquedesign. The joint brace contains sturdy uprights that provide stabilityto the wearer. In a preferred embodiment, straps containing air-cellssecurely hold the brace in position on the user's body, whiledistributing pressure evenly over the area of the air-cell to preventwearer discomfort or injury.

The joint brace described herein comprises a hinged movement arm, ameans for allowing controlled free movement through the movement armhinge about a predetermined range of motion, a hinged drive arm, a meansfor releasably locking said drive arm hinge at a predetermined angle,and adjustable means for connecting said movement arm to said drive armsuch that the hinges thereof are in alignment. The means for allowingcontrolled free movement through the movement arm hinge can comprise arange of motion assembly associated with the movement arm hinge. Themeans for releasably locking the drive arm can comprise a novel lockingmechanism associated with the drive arm hinge that can be used toimmobilize a joint by locking the brace into a fixed position. The novellocking mechanism can be switched easily from a locked to an unlockedposition, without any time-consuming procedures involving insertionand/or removal of pins into the brace. In the locked position, the bracecan statically stretch the joint in either flexion or extension. Thebrace comprises an angle-adjustment means that can be adjusted so thatthe brace achieves the desired angle of flexion or extension. Theangle-adjustment mechanism can comprise a detailed scale so that thedegree of extension and flexion can be closely monitored. The staticstretch feature provides the benefits of stability and protection whilepreparing the joint for eventual movement.

An advantage of the novel design of the brace is that the lockingmechanism can be disengaged while the brace is positioned on a wearer toprovide the wearer with free movement of the joint within the naturalaxis of movement while preventing the joint from moving in a directionoutside of the joint's natural axis of movement. The range of motionassembly can be adjusted to set the maximum and minimum angle throughwhich the joint can move in flexion and/or extension. Limiting themaximum and minimum angle of motion ensures that the wearer does notexceed predetermined limits, which could injure the joint. The braceadvantageously performs the multiple functions of protection,immobilization, static stretching, and controlled free movement of ajoint.

The brace can be adjusted easily to fit either the right or left side ofa wearer's body, and to fit a wearer of small or large body size.Further, the novel locking mechanism contains no bulky motors or heavysprings, and in a preferred embodiment the adjustment knob of thelocking mechanism easily can be removed and reattached as needed for thecomfort of the wearer.

The brace also comprises an override means that prevents damage to thelocking mechanism when the brace is subjected to a large external force.

These and other advantages of the present invention will become morefully apparent by examination of the following description of thepreferred embodiments and the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

To better understand the invention, a more particular description of theinvention will be rendered by reference to the appended drawings. Thesedrawings only provide information concerning typical embodiments of theinvention and are not to be considered limiting of its scope. Theinvention will be described and explained with additional specificityand detail through the use of the accompanying drawings, in which:

FIG. 1 is an isometric view of one embodiment of the brace in theextended 180° position, with the attachment straps omitted for clarity;

FIG. 2 is a partially exploded isometric view of the brace of FIG. 1;

FIG. 3 is an exploded isometric view of the brace drive arm and lockingmechanism of FIG. 1;

FIG. 3 a is an isometric view of the cam shaft of the locking mechanismof FIG. 3;

FIG. 3 b is an isometric view of the external tooth gear of the lockingmechanism of FIG. 3;

FIG. 3 c is an isometric view of the spline plate member of the lockingmechanism of FIG. 3;

FIG. 3 d is a rear view of the concave side of the thumb lever of thelocking mechanism of FIG. 3;

FIG. 3 e is an isometric view of the concave side of the joint/splineinterface member of the locking mechanism of FIG. 3;

FIG. 3 f is a cross-sectional view of one embodiment of a knob of thelocking mechanism of FIG. 3;

FIG. 3 g is an isometric partially cut away view of the lockingmechanism in the locked position;

FIG. 3 h is a cross-sectional view of the locking mechanism in thelocked position;

FIG. 3 i is an isometric partially cut away view of the lockingmechanism in the unlocked position;

FIG. 3 j is a cross-sectional view of the locking mechanism in theunlocked position;

FIG. 4 is a plan view of the end strap used with the brace;

FIG. 5 is a plan view of an air bladder useful with the brace of thepresent invention;

FIG. 6 is a plan view of the slot strap used with the brace of FIG. 1;

FIG. 7 is a view of an embodiment of the brace of the instant inventionbeing applied to the arm of a wearer with the end straps secured and theslot straps unsecured; and

FIG. 8 is a view of the brace of FIG. 7 being positioned on the arm andthe slot straps being adjusted to obtain proper brace alignment with theelbow joint of the wearer.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

The following detailed description is of an embodiment of the inventionwherein the multi-functional brace is adapted for use with an elbow. Itis to be understood, however, that the invention is not so limited. Forexample, those skilled in the art will understand how to adapt theprinciples of the invention as disclosed herein to create amulti-functional brace for use with a knee or any other joint.

Reference is now made to the figures wherein like parts are referred toby like numerals throughout. With particular reference to FIG. 1, amulti-functional elbow brace 10 according to the present inventioncomprises a hinged movement arm 12 and a hinged drive arm 14. Adjustablemeans for connecting hinged movement arm 12 and hinged drive arm 14comprise adjustable cross brackets 16. Brace 10 comprises a proximalportion 11 and a distal portion 13. In some embodiments, the proximalportions of hinged movement arm 12 and hinged drive arm 14 can be widerthan the distal portions thereof.

With reference now to FIG. 2, hinged movement arm 12 comprises a firstarm member 18 and a second arm member 20 joined by a means for allowingcontrolled free movement of the movement arm through a predeterminedrange of motion; such means can be in the form of range of motionassembly 21. The first arm member 18 comprises radially enlarged end 19having an arcuate cavity 22 formed therein. The second arm member 20comprises radially enlarged end 23 having a series of holes 24 formedtherein, preferably arranged in a circle or other arcuate configuration.The first and second arm members 18, 20 each comprise two strap slots26, an axis connection hole 28, a bracket connection hole 30 and twobracket bosses 32 on their inwardly facing surfaces. The bosses 32 canbe in the form of small pins that extend through pinholes in the arms,such that the protruding ends of the pins extend from the inner surfacesof the arms. The first arm member 18 is connected to the second armmember 20 by an axial connection means which can comprise means such asa screw, a bolt, or in the illustrated embodiment, an axis rivet 33 incombination with axis washer 31. As may be seen, axis rivet 33 isinserted through the axis connection hole 28 in first arm member 18,through axis washer 31, and into axis connection hole 28 in second armmember 20. Range of motion assembly 21 comprises radially enlarged end19 of first arm 18, radially enlarged end 23 of second arm 20, theirconnecting means 33, arcuate cavity 22, holes 24, and one or morerange-limiting pins (not shown) that can be inserted through arcuatecavity 22 into one or more of the holes 24. Upon flexion or extension ofthe user's limb, a range-limiting pin will contact one or another end ofarcuate cavity 22, preventing further movement. In the absence ofrange-limiting pins, there would be unobstructed full rotation betweenfirst arm member 18 and second arm member 20. It will be appreciatedthat, while in the illustrated embodiment the arcuate cavity 22 is inend 19 of first arm 18 and holes 24 are in end 23 of second arm 20, thedesign could be reversed so that the arcuate cavity is in end 23 ofsecond arm 20 and holes 24 are in end 19 of first arm 18.

Adjustable means for connecting movement arm 12 and drive arm 14 cancomprise proximal and distal adjustable brackets 16. In the illustratedembodiment, each adjustable bracket 16 comprises a fixed inner L-shapedflange member 34 having legs 34 a, 34 b, and an adjustable outerL-shaped flange member 36 having legs 36 a, 36 b. Leg 34 a of innerflange member 34 comprises an adjustment screw hole 38 and two outwardlyextending adjustment bosses 40. Leg 34 b of inner flange member 34comprises a brace connection boss 42 having a threaded interior, twoboss acceptor holes 44, and a strap-connector hole 46. The outer flangemember 36 preferably comprises ten adjustment-boss acceptor holes 48 andbrace-adjustment slot 50 on leg 36 a thereof, and a brace connectionboss 42 with a threaded interior and two boss acceptor holes 44 on leg36 b thereof.

Inner flange member 34 is adjustably connected to outer flange member 36by means of brace-adjustment screw 52 that extends through a washer 45,through brace-adjustment slot 50 and then into adjustment screw hole 38formed in leg 34 a of upper flange member 34. The width of theadjustable bracket 16 can be varied by inserting the outwardly extendingadjustment bosses 40 of leg 34 a into the different adjustment-bossacceptor holes 48 in leg 36 a before tightening brace-adjustment screw52. Thus the width of bracket 16 can be adjusted to fit the diameter ofa wearer's limb.

Hinged drive arm 14 (FIG. 2) comprises third arm member 54 and fourtharm member 56, pivotably joined by a means for releasably locking saidhinged drive arm at a predetermined angle; such releasable locking meanscan be in the form of locking mechanism 57. As shown in FIG. 3, thirdarm member 54 has an enlarged circular recessed section 53 at one end.Fourth arm member 56 has an enlarged circular section 55 at one end.Both the third and fourth arm members 54, 56 comprise arm strapconnection holes 58, a bracket connection slot 60, and two bracketbosses 32. When third and fourth arm members 54, 56 are assembledtogether as drive arm 14, circular sections 53 and 55 form part oflocking mechanism 57, described in detail below.

Adjustable brackets 16 connect the movement arm 12 and drive arm 14.Referring again to FIG. 2, the inner L-shaped flange member 34 of eachadjustable bracket 16 is mounted to the drive arm 14 by inserting braceconnection boss 42 on bracket leg 34 b into the bracket connection slot60, and inserting the bracket bosses 32 on the third and fourth arms ofdrive arm 20 into the boss acceptor holes 44. Bracket connection screw62 is inserted through the bracket connection slot 60 and into thethreaded interior of the brace connection boss 42. The outer flangemember 36 of the adjustable bracket 16 is mounted to the movement arm 12by inserting the brace connection boss 42 into the bracket connectionhole 30, and inserting the bracket bosses 32 into the boss acceptorholes 44. The bracket connection screw 62 is inserted through thebracket connection hole 30 and into the threaded interior of the braceconnection boss 42. It may be seen that the assembled brace 10 can beapplied to a user on either the right or left limb, and with the lockingmechanism on either the medial or lateral side of the limb. Inparticular, before the brace is applied to the user the adjustablebrackets 16 can be rotated 180 so that the brackets 16 face downwardrather than upward as viewed in FIG. 2. The brace 10 then can be turnedover and applied to the opposite limb of the user with the proximalportion 11 thereof still proximal to the user, and the distal portion 13thereof still distal to the user, and with the locking mechanism 57disposed away from the user's body. In this way, the same brace can beapplied to either a left or a right limb, and with the locking mechanismon either the medial side or the lateral side of either limb, at theuser's preference.

With reference now to FIGS. 3 and 3 a-j, the locking mechanism 57 islocated at the rotational axis between third arm member 54 and fourtharm member 56. An internal tooth gear 64 has bosses 66 on one side nearits perimeter, which bosses engage internal-tooth gear boss acceptorholes 68 located on the inside of recessed circular section 53 of thirdarm member 54. With reference now to FIG. 3 b, an external tooth gear 70comprises external teeth 88, an internal locking gear 96, and an axialtubular portion 76 that fits snugly onto larger diameter portion 74 ofcam shaft 72, shown in FIG. 3 a. With reference to FIGS. 3, 3 h, and 3j, the cam shaft boss on the opposite end of larger diameter portion 74of cam shaft 72 is received in axis hole 78 of third arm member 54 andinto a shoulder bearing 82. Screw 84 is inserted through washer 86 andthe shoulder bearing 82 and into a threaded opening in the cam shaftboss. The external teeth 88 on the external tooth gear 70 fit inside ofthe internal tooth gear 64 forming a wobble gear. Only some of theexternal teeth 88 engage the teeth of internal tooth gear 64 at any onetime. The wobble gear ratio can be in the range of about 20:1 to about30:1. In one preferred embodiment, the joining of the internal toothgear 64 and the external tooth gear 70 creates a wobble gear with a 24:1ratio. Thus, rotating the external tooth gear 70 twenty-four timescauses the internal tooth gear 64 to rotate a full 360°.

Axial tubular portion 76 of external tooth gear 70 fits within a gearmember in the form of an annular spline plate member 92, with coilspring 90 disposed therebetween. With reference now to FIG. 3 c, theannular spline plate member 92 comprises spline plate axially protrudingteeth 94 which face the internal locking gear 96 of the external toothgear 70. Coil spring 90 biases the annular spline plate member 92 awayfrom external tooth gear 70 so that the spline plate extruding teeth 94do not engage the internal locking gear 96 of external tooth gear 70unless a counter-pressure is applied. The annular spline plate member 92comprises four ramped cam surfaces 97 opposite the spline plateprotruding teeth 94, each ramped cam surface 97 comprising aramp-locking groove 99. The spline plate member 92 further comprisesfour axially directed slots 100 around its perimeter. Circular end 55 offourth arm member 56 has a substantially circular orifice with fouraxially extending tabs 98 along the perimeter. The spline plate member92 engages fourth arm member 56 by means of the four axially extendingtabs 98 that fit into the four axially directed spline plate slots 100.The cam shaft 72, including the clip recess 75 therein, extends throughexternal tooth gear 70, through the center of annular spline plate 92,and through the orifice in circular end 55 of fourth arm member 56.

With reference now to FIG. 3 d and FIG. 3 e, a concave annular thumblever 104 comprises two diametrically opposed interface-gripping tabs105 on its inner circumference and a thumb knob 107 on its outercircumference. A concave annular lever/spline interface member 106 shownin FIG. 3 e comprises two axial grooves 108 diametrically opposed on itsouter circumference, and four ramp-engaging tabs 110 on its innercircumference. (It is pointed out that in FIG. 3 e the interface member106 is shown in an orientation opposite that shown in FIG. 3, so thatthe structure within the concave surface is more readily understood bythe viewer.) An override means is provided, the override means beingshown in the illustrated embodiment as wave spring 102. Wave spring 102may be inserted into the inner circumference of the thumb lever 104. Thelever/spline interface member 106 is inserted into the innercircumference of the thumb lever 104 so that the wave spring 102 isbetween the thumb lever 104 and the lever/spline interface member 106.The exterior grooves 108 on the lever/spline interface member 106receive the interface-gripping tabs 105 on the inner circumference ofthumb lever 104. Both the thumb lever 104 and the lever/spline interfacemember 106 are oriented with their concave inner surfaces facing theexternal tooth gear 70. The annular edge of thumb lever 104 is incontact with circular end 55 of fourth arm member 56. The annular edgeof the lever/spline interface member 106 engages the ramped cam surfaces97 of the spline plate member 92. The wearer can push the thumb knob 107to rotate the thumb lever 104 between a locked and an unlocked position,as described more fully below.

The angle between the third arm member 54 and the fourth arm member 56of drive arm 14 and the corresponding angle between the first arm member18 and the second arm member 20 of movement arm 12 can be locked byengaging the locking mechanism 57. The locking mechanism 57 is operatedby engaging the thumb knob 107 to rotate thumb lever 104. Because theinterface gripping tabs 105 on the interior of thumb lever 104 arereceived in exterior grooves 108 on interface member 106, rotating thethumb lever 104 by means of thumb knob 107 also rotates the lever/splineinterface member 106. As lever/spline interface member 106 rotates, theramp-engaging tabs 110 on the inner surface thereof move along theramped cam surfaces 97 located on the spline plate member 92. The forceexerted by the ramp-engaging tabs 110 against the ramped cam surfaces 97urges the spline plate member 92 toward the external tooth gear 70. Theforce exerted by the ramp-engaging tabs 110 overcomes the counter-forceexerted by the coil spring 90 until the spline plate protruding teeth 94engage the internal locking gear 96 of external tooth gear 70. When theramp-engaging tabs 110 move a sufficient distance along the ramped camsurfaces 97, the ramp-engaging tabs 110 move against the ramp-lockinggrooves 99 of spline plate member 92. The counter force exerted by thecoil spring 90 against the opposite surface of spline plate member 92maintains the ramp-locking grooves 99 of spline plate member 92 inengagement with the ramp-engaging tabs 110 of interface 106. When thespline plate protruding teeth 94 engage the internal locking gear 96,the third arm member 54 and the fourth arm member 56 cannot rotatefreely around each other, and the angle between the two is fixed.Rotating the thumb lever 104 in the opposite direction disengages thespline plate protruding teeth 94 from the internal locking gear 96, andthe third arm member 54 can rotate freely with respect to the fourth armmember 56 about the axis between the two. This occurs because therotation of the thumb lever 104 rotates the interface 106 which removesthe force of the ramp-engaging tabs 110 on the spline plate member 92 asthey move along the ramped cam surfaces 97. When the angle between thearms is unlocked, free-range-of-motion therapy, controlled by range ofmotion assembly 21, can be performed on the wearer's joint, even thoughthe wearer does not remove the brace. When the angle between the arms islocked by operation of thumb lever 104, static stretch therapy can beperformed on the wearer's joint in either flexion of extension. Thebrace can be locked at any angle desired for appropriate stretchtherapy, moreover, this angle can be adjusted from time to time aseffective therapy requires.

The invention described herein further comprises an angle-adjustmentmeans that allows the static stretch therapy angle to be adjusted evenwhen the locking mechanism 57 is locked. As shown in FIG. 3 f, a knob112 comprises a knob shaft 114. As shown in FIG. 3, the knob shaft 114is inserted through retaining ring 116, washer 118, annular thumb lever104, wave spring 102 and annular lever/spline interface member 106, andinserted into a knob connection means operatively coupled to cam shaft72. In the illustrated embodiment, knob connection means is in the formof clip 120.

When the locking mechanism 57 is in the locked position, the fixed anglebetween the third arm member 54 and the fourth arm member 56 can bechanged by rotating the knob 112 in the desired direction. Because theknob 112 is operatively connected to the cam shaft 72, rotating the knob112 rotates the cam shaft 72 in the same direction. The rotation of thecam shaft 72 rotates the external tooth gear 70 as a wobble gear insidethe internal tooth gear 64. In the preferred embodiment, a 24:1 ratio ofthe external tooth gear 70 to the internal tooth gear 64 requirestwenty-four rotations of the knob 112 to rotate the fourth arm member 56in a 360° arc around the third arm member 54. The adjustment of theangle allows the static stretch of the joint to be increased ordecreased in either flexion or extension. In another preferredembodiment, the fourth arm member 56 has a calibrated scale at itscircular end 55 and the third arm member 54 has a calibration mark. Thescale and mark convey the angle between the fourth arm member 56 andthird arm member 54. This scale and mark allow the user to monitor thedegree of extension and flexion of the joint.

Once the desired angle of flexion or extension has been selected and thebrace has been locked into position, the knob 112 can be removed fromthe brace 10 for the convenience and comfort of the wearer. The knob 112is connected to the brace 10 by the knob shaft 114 inserted into theclip 120, which in turn is inserted into the clip recess 75 of the camshaft 72. The clip 120 is adequate to maintain a connection between theknob shaft 114 and the cam shaft 72 during normal use of the elbowbrace. When a force in the direction opposite the cam shaft 72 isapplied to the knob 112, the clip 120 no longer maintains the connectionbetween the knob shaft 114 and the cam shaft 72. Removing the knob 112can create greater comfort and convenience for the wearer. Inparticular, removing the knob 112 allows the wearer to place thumb lever104 against the wearer's body without injury from an exposed shaft. Theknob 112 easily can be re-attached to the brace by placing the knobshaft 114 into the clip 120 at the clip recess 75 on the cam shaft 72,and applying force toward the cam shaft 72. Other means for easymechanical detachment and reattachment of the knob will be known tothose skilled in the mechanical arts. In the embodiment shown in FIGS. 3h and 3 i, the knob 112 a does not have a shaft, but instead is receivedon a protruding shaft 119. While this embodiment performs the exact samefunction in terms of operating the lock mechanism as described below,removable of the knob 112 a may not be as desirable because the exposedconnection means 119 does not provide a low-profile surface, and may betroublesome to the wearer.

An override means that prevents damage to the locking mechanism 57 fromforce applied to the brace while the locking mechanism 57 is in thelocked position comprises wave spring 102. The wave spring 102 allowsthe engaged spline plate protruding teeth 94 to temporarily disengagefrom the internal locking gear 96 if a significant external force isapplied to the elbow brace. The disengagement occurs when thelever/spline interface member 106 moves against the force of the wavespring 102 and into the thumb lever 104, allowing the ramp-engaging tabs110 to move out of the ramp-locking grooves 99, which allows the coilspring 90 to push the spline plate member 92 away from the externaltooth gear 70. This disengagement protects the spline plate protrudingteeth 94 and the internal locking gear 96 from breakage in the event aforce greater than the failure point of the apparatus is applied.

The range of motion assembly 21 created in part by the cavity 22 and theholes 24 can limit the range of the angles of free movement of thedistal portion 13 of the brace relative to the proximal portion 11. Thisrange of angles can be limited by inserting range-limiting pins (notshown) through the cavity 22 and into one or more holes 24. Uponrotation, a range-limiting pin will contact the upper or lower edge ofthe cavity 22, preventing further rotation. The range of motion assembly21 can limit the maximum and minimum angle whether the locking mechanism57 is locked or unlocked. The range of motion assembly 21 also can lockthe elbow brace into one angle by appropriate placement therange-limiting pins.

In the preferred embodiment, straps attach the brace 10 to the wearer.For example, in the embodiment in which the brace is adapted for use ona wearer's arm, there can be four straps located respectively at thewearer's wrist, forearm, bicep, and upper arm. The wearer's bicep andupper arm are placed on the proximal portion 11 of the brace comprisingfirst arm member 18 and third arm member 54, while the wearer's wristand forearm are placed on the distal portion 13 of the brace comprisingthe second arm member 20 and the fourth arm member 56. There are twotypes of straps used in the illustrated embodiment. End straps 122 areused at the ends of the brace, i.e., at the wrist and upper armlocations, where the adjustable cross brackets are located. Slot straps128 are used at the bicep and forearm portions of the brace.

With reference now to FIG. 4, an end strap 122 is provided, comprising astrap reinforcement 124 welded near one end of a strip 123 of loopbearing material having a tab portion 126 of hook bearing material atits opposite end. Referring to FIG. 2, end strap 122 is attached to thethird arm member 54 by inserting a rivet, not shown, through strapreinforcement 124 and strap-connector hole 46 in leg 34 b of bracket 16.A D-ring, not shown, is affixed to the exterior surface of first arm 18;the bracket connection screw 62 that fits into bracket connection hole30 of first arm 18 can be used for this purpose. The same means are usedto attach a second end strap 122 to the wrist portion of fourth arm 56.Because the adjustable cross brackets 16 extend underneath the wearer'sarm at these locations, the end straps 122 need only extend over the topof the wearer's upper arm and wrist, respectively. When the brace 10 isapplied to a user, the end straps 122 are looped through the D-rings andthe hook bearing tab 126 engages the loop bearing strip 123 so as tosecure the brace 10 comfortably to the user.

With reference now to FIG. 6, an elongated slot strap 128 comprises astrap reinforcement 124 welded somewhat off-center to a strip 123 ofloop-bearing material. Hook bearing tabs 126 are on either end of loopbearing strip 123. With reference now to FIG. 2, the slot straps 128 arefastened to third arm member 54 and fourth arm member 56 by a connectionmeans such as a rivet, not shown, that passes through reinforcement 124and then into arm strap connection hole 58 located on the third armmember 54 and fourth arm member 56. Due to the off-center placement ofreinforcement 124, each slot strap 128 will have a longer portion and ashorter portion. Generally, the longer portion of the slot strap 128will extend over the wearer's bicep while the shorter portion willextend under the wearer's arm. The hook-bearing ends 126 of each slotstrap 122 are threaded through strap slots 26 located on the first armmember 18 and second arm member 20, respectively. Each slot strap 128 isfolded back upon itself and secured by pressing the hook bearing tab 126against loop bearing strip 123.

In one preferred embodiment, an aircell or bladder 130 filled with airis connected to the end straps 122 and/or the slot straps 128. Withreference now to FIG. 5, a preinflated air bladder 130 comprises twopieces of flexible air-impervious plastic 131, 133 sealed at theirperimeters such as with an RF seal 135. Advantageously, the preinflatedair bladder can have a piece of soft foam 137 between plastic 131, 133for ease of manufacture, to maintain the inflation of the bladder, andto further promote the user's comfort. A fabric covering 138 over atleast one of the plastic pieces 133 is provide with slits 139 forreceiving straps 122 or 128 in belt-loop fashion. The use of such airbladders is illustrated in FIGS. 7 and 8. The air bladder 130 helpsincrease the wearer's comfort and helps secure the brace to the wearer'slimb by distributing the load of the strap.

While this invention has been described in connection with a preferredembodiment, it is clearly to be understood that this is done only by wayof example and not as a limitation to the scope of our invention as setforth in the objects thereof and in the appended claims. For example, itwill be appreciated that the disclosed brace can be modified for usewith a knee or other joint.

1. A joint brace for providing therapy to an injured joint, such jointbrace comprising (a) a hinged movement arm; (b) means at said movementarm hinge for allowing controlled free movement through the movement armhinge about a predetermined range of motion; (c) a hinged drive armhaving first and second arms; (d) means at said drive arm hinge forreleasably fixing the first arm with respect to the second arm at apredetermined angle; and (e) adjustable means for connecting saidmovement arm to said drive arm such that the hinges thereof are inalignment.
 2. The joint brace of claim 1 wherein said releasable fixingmeans comprises a first gear member, a second gear member, and a levermeans operable on said first gear member to cause said first gear memberto be engaged or disengaged from said second gear member, whereby whensaid first gear member is engaged with said second gear member saidhinged drive arm is locked, and when said first gear member is notengaged with said gear member said hinged drive arm is unlocked.
 3. Thejoint brace of claim 2 wherein said first gear member further comprisesat least one cam surface by which the movement of said lever means istransmitted to cause said first gear member to engage and disengage fromsaid second gear member.
 4. The joint brace of claim 3 furthercomprising an interface member that operatively couples said lever meansto said at least one cam surface of said first gear member.
 5. The jointbrace of claim 4 further comprising an override means disposed betweensaid lever means and said interface member.
 6. The joint brace of claim3 wherein said second gear member being operatively coupled to one ofsaid arms and said first gear member being operatively coupled to theother arm, such that engagement of said first and second gear membersserves to lock said first and second arms with respect to one another.7. The joint brace of claim 1 further comprising means for adjusting thehinge angle of said drive arm, said adjusting means being operable whensaid releasable fixing means has fixed the first and second arms withrespect to each other.
 8. The joint brace of claim 7 wherein saidadjusting means comprises a rotatable knob operatively coupled to atleast one of said first and second arms, such that rotation of said knobcauses rotation of said at least one arm about said drive arm hinge. 9.The joint brace of claim 8 wherein said rotatable knob is operativelycoupled to said at least one arm by a wobble gear.
 10. The joint braceof claim 9 wherein said wobble gear comprises an external tooth gear andan internal tooth gear and ratio of the external tooth gear to theinternal tooth gear is in the range of about 20:1 to about 30:1.
 11. Thejoint brace of claim 10 wherein said wobble gear ratio is 24:1.
 12. Thejoint brace of claim 8 wherein said rotatable knob is removable.
 13. Thejoint brace of claim 1 wherein said hinged movement arm comprises afirst movement arm member and a second movement arm member in hingedengagement, and said means for allowing controlled free movement throughthe movement arm hinge comprises means for limiting rotation of saidfirst and second movement arm members with respect to one another aboutsaid movement arm hinge.
 14. The joint brace of claim 13 wherein saidmeans for limiting rotation comprises an arcuate cavity on one of saidmovement arm members, said arcuate cavity having two ends, at least onehole on said other movement arm member, said hole being alignable withan area of said arcuate cavity, and at least one pin member extendablethrough said at least one hole and said arcuate cavity, such thatrotation of said first and second movement arm members with respect toone another will cause said pin member to engage one or the other end ofsaid arcuate cavity, thereby limiting said rotation of said first andsecond arm members with respect to one another.
 15. The joint brace ofclaim 1 further comprising at least one strap for securing said brace toa wearer.
 16. The joint brace of claim 15 wherein a pre-inflated bladderis disposed between said at least one strap and a wearer.
 17. The jointbrace of claim 15 wherein said strap comprises a portion of hook-bearingmaterial and a portion of loop bearing material.
 18. The joint brace ofclaim 15 wherein said strap is operatively mounted to said drive arm andsaid movement arm is provided with means for receiving said straptherethrough.
 19. The joint brace of claim 1 wherein said adjustableconnection means comprises a first member coupled to said drive arm anda second member coupled to said movement arm, said first and secondadjustable connection means members being engageable with one another atmore than one location therein, whereby the width of the adjustableconnection means can be varied.
 20. The joint brace of claim 19 whereinsaid adjustable connection means can be rotated 180° with respect tosaid drive arm and said movement arm, whereby said joint brace can beadapted for use on either a right or left limb of a user.
 21. A jointbrace for providing therapy to an injured joint, such joint bracecomprising a movement arm having a first hinge; an assembly at the firsthinge for controlling movement of the movement arm within apredetermined range of motion about the first hinge; a drive arm havinga second hinge; a locking mechanism at the second hinge for releasablylocking the second hinge at an angle; and an adjustable bracket forconnecting the movement arm to the drive arm such that the first andsecond hinges are in alignment.